FIGS. 1-3 depict prior art arrangements for closing an end of a muffler tube, such as a perforated muffler tube for a side-in and side-out muffler. FIG. 1 depicts a prior art plug flange A fitted in the end of a muffler tube B. During assembly, the plug flange A is inserted into the end of the tube B and spot welded in place at weld points C. FIGS. 2 and 3 illustrate additional examples of prior art plug flanges D, E inserted into the end of tubes F, G, respectively, and spot welded in place.